How to Tell if Star Polyps are Happy and Healthy?

I am new to saltwater and got my first coral 3 days ago. The local fish store said they were green star polyps but they were more tan/pink in color with only very faded light green tips, so I'm thinking they may be a pink voriety or something. Anyway, it has been three days and all but 3 or 4 are now wide open (most opened the next morning after I got them which is a good sign). I don't know much about corals (thought I try to educate myself as best I can through reading and such). how do I know if my polyps are happy and healthy? Any good signs to look for? Personally I think they are looking great but again, I've never had any corals before. thanks.

 

Polyps fully open and growth of new polyps is all you can ask for.